Electrical connection box with water drainage structure for use in a vehicle

Abstract

An electrical connection box for use in a vehicle, particularly a car, has a casing, and a stack of bus bars and insulation plates alternating in a vertical direction. For drainage of water penetrating onto the stack, each insulation plate has a drainage aperture and a drainage wall extending downwardly from its aperture so as to define and surround a drainage passage. At least each of the insulation plates below the upper plate has on its upper surface a flow interruption rib upstanding continuously around its drainage aperture. Water on one bus bar does not connect the bus bar conductively to another bus bar.

What is claimed is: 
     
       1. An electrical connection box for use in a vehicle, comprising: a casing;   a plurality of bus bars; and   a plurality of insulation plates having upper and lower surfaces, said bus bars and said insulation plates being arranged in said casing as a vertical stack in which said insulation plates alternate in the vertical direction with said bus bars,   wherein each insulation plate in said vertical stack has a drainage aperture and a drainage wall extending downwardly from said drainage aperture thereof so as to define and surround a drainage passage from said drainage aperture, and   at least each insulation plate below an upper insulation plate in said vertical stack has on its upper surface a flow interruption rib between each said drainage aperture and each said bus bar, each said interruption rib extending upwardly from said drainage aperture and said insulation plate.   
     
     
       2. The electrical connection box according to claim 1, wherein each said flow interruption rib is spaced from each said drainage aperture, and said drainage wall of each insulation plate contacts an upper surface of a next lower insulation plate in said vertical stack between said flow interruption rib and said drainage aperture of said next lower insulation plate, and said drainage walls and drainage apertures together form a continuous drainage path extending to a bottom of the vertical stack. 
     
     
       3. The electrical connection box according to claim 2, wherein the upper insulation plate in said vertical stack includes on its upper surface a flow interruption rib upstanding around said drainage aperture thereof. 
     
     
       4. The electrical connection box according to claim 1, wherein each drainage wall of each respective insulation plate extends to the bottom of said vertical stack through said drainage aperture of each insulation plate positioned lower in the vertical stack, said drainage wall of each respective insulation plate surrounding said drainage wall of each insulation plate positioned higher in the vertical stack. 
     
     
       5. The electrical connection box according to claim 1, wherein each drainage wall and each flow interruption rib is cylindrical in shape. 
     
     
       6. An electrical connection box for use in a vehicle, comprising: a casing;   a plurality of bus bars; and   a plurality of insulation plates having upper and lower surfaces, said bus bars and said insulation plates being arranged in said casing as a vertical stack in which said insulation plates alternate in the vertical direction with said bus bars, wherein   each insulation plate in said vertical stack has a drainage aperture and a drainage wall extending downwardly from said drainage aperture thereof so as to define and surround a drainage passage from said drainage aperture, and   said drainage wall of each insulation plate contacts an upper surface of a next lower insulation plate in said vertical stack adjacent said drainage aperture of said next lower insulation plate, said drainage walls and drainage apertures together forming a continuous drainage path extending to a bottom of the vertical stack.   
     
     
       7. An electrical connection box for use in a vehicle, comprising: a casing;   a plurality of bus bars; and   a plurality of insulation plates having upper and lower surfaces, said bus bars and said insulation plates being arranged in said casing as a vertical stack in which said insulation plates alternate in the vertical direction with said bus bars, wherein   each insulation plate in said vertical stack has a drainage aperture and a drainage wall extending downwardly from said drainage aperture thereof so as to define and surround a drainage passage from said drainage aperture, and   each drainage wall of each respective insulation plate extends to the bottom of said vertical stack through said drainage aperture of each insulation plate positioned lower in the vertical stack, said drainage wall of each respective insulation plate surrounding said drainage wall of each insulation plate positioned higher in the vertical stack.